Practice Quiz PHYSICS Yr 8

What will a substance do when it is heated?

• It will expand

• It will contract

• It will burn

• It will explode

When a liquid is evaporating it cools down. Why?

• The faster particles escape leaving the slower particles behind

• There are fewer particles

• Evaporation needs a breeze and breezes cool things down

• It has a smaller volume than before

Why does hot air rise?

• Heat naturally goes upwards

• It is pushed there by the cold air

• It is less dense than colder air

• It doesn't, this is a myth

On ray diagrams, what is the normal?

• An imaginary line at 90^o to the reflecting surface

• An imaginary line at 45^o to the reflecting surface

• A real line at 90^o to the reflecting surface

• A real line at 180^o to the reflecting surface

What is a virtual image?

• An image that can be projected onto a screen

• An image that can't be projected onto a screen

• An image that is virtually perfect

• An image of a person only

Choose the correct formula for pressure from the options below.

• Area over force

• Force over area

• Force times areaForce times area

What is needed in order to lower the pressure of water at the bottom of a swimming pool?

• Add more water

• Take some water out

• Decrease the area of the swimming pool

What happens when light goes from one medium to another that is more dense than the first, for example, from air to water?

• It slows down

• It speeds up

• Nothing

What colour light do you get when you mix red, green and blue light?

• Cyan

• Black

• White

Select the primary colours from the list below.

• Red

• Cyan

• Green

• Blue